39,
1. It was pre-scanning days.
2. Now you can merely scratch off a bar (prior to applying the sticker), forcing the meter maids to write it out manually.
3. If the summons has an incorrect plate #, the ticket was effectively never written against your vehicle and you can discard it.
4. If you choose to challenge it, it is legally flawed (in NYC at least) and an ALJ will dismiss it.